There was an unexpected error (type=Internal Server Error, status=500)
Whitelabel Error Page This application has no explicit mapping for /error, so you are seeing this as a fallback. Wed Jan 15 17:18:28 CST 2020 There was an unexpected error (type=Internal Server Error, status=500). 500 null
报错500，错误可能为 后台 sql 语句书写错误
获取不到 db_source 的值，改为固定的值
文章来自：https://www.cnblogs.com/shiliuhuanya/p/12197865.html